Fasting

Bukhari :: Book 3 :: Volume 31 :: Hadith 199

Narrated Mujahid from 'Abdullah bin 'Amr:

The Prophet said (to 'Abdullah), "Fast three days a month."
'Abdullah said, (to the Prophet) "I am able to fast more than
that." They kept on arguing on this matter till the Prophet said,
"Fast on alternate days, and recite the whole Qur'an once a month."
'Abdullah said, "I can recite more (in a month)," and the argument
went on till the Prophet said, "Recite the Qur'an once each three
days." (i.e. you must not recite the whole Qur'an in less than
three days).